Ammonoids from the Tully Formation and Harrell Shale in Pennsylvania: Markers of sea-level highstands in the Middle to Late Devonian transition, Appalachian foreland basin, eastern North America

The Kettle Point Formation of southwestern Ontario consists of intervals of organic-rich interlaminated black shale interbedded with organic-poor greyish green mudstones and rare red beds, separated by metre-scale sequences of non-interlaminated black shale. The formation shows a largely consistent background value for the black shales around −20‰ δ34S, punctuated by a substantial positive excursion of ∼32‰ (up to +12.87‰) that coincides with a significant interval of greyish green mudstone and red beds. Lithological and geochemical data indicate that the black shales were deposited during periods of anoxia, with thick intervals of non-interlaminated black shales recording the peak of anoxia, whereas the greyish green mudstones record deposition in more oxygenated environments. Relative water depth is interpreted as the key control on the vertical and lateral distribution of the Kettle Point lithofacies. Interbedded black shales and greyish green mudstones were deposited in relatively shallow waters, where minor, short-lived falls in relative sea level promoted dysoxic to oxic conditions and the deposition of organic-poor lithologies. Non-interlaminated black shales are indicative of substantial rises in relative sea level, resulting in widespread anoxia and the deposition of thicker and more laterally extensive packages of organic-rich sediment. The formation of black shales in relatively shallow waters in southwestern Ontario implies that the extensive deposition of organic-rich sediment across eastern North America during the Late Devonian was a product of widespread anoxia related to restricted circulation in intracratonic and foreland basin depositional centers.

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A radiocarbon chronology of Holocene climate change and sea-level rise at the Delmarva Peninsula, US Mid-Atlantic Coast

The Holocene ◽

10.1177/09596836211048282 ◽

2021 ◽

pp. 095968362110482

Author(s):

Kelvin W Ramsey ◽

Jaime L. Tomlinson ◽

C. Robin Mattheus

Keyword(s):

Climate Change ◽

North America ◽

Sea Level Rise ◽

Sea Level ◽

Early Holocene ◽

Eastern North America ◽

Delmarva Peninsula ◽

The Holocene ◽

Cool Climate ◽

And Sea Level

Radiocarbon dates from 176 sites along the Delmarva Peninsula record the timing of deposition and sea-level rise, and non-marine wetland deposition. The dates provide confirmation of the boundaries of the Holocene subepochs (e.g. “early-middle-late” of Walker et al.) in the mid-Atlantic of eastern North America. These data record initial sea-level rise in the early Holocene, followed by a high rate of rise at the transition to the middle Holocene at 8.2 ka, and a leveling off and decrease in the late-Holocene. The dates, coupled to local and regional climate (pollen) records and fluvial activity, allow regional subdivision of the Holocene into six depositional and climate phases. Phase A (>10 ka) is the end of periglacial activity and transition of cold/cool climate to a warmer early Holocene. Phase B (10.2–8.2 ka) records rise of sea level in the region, a transition to Pinus-dominated forest, and decreased non-marine deposition on the uplands. Phase C (8.2–5.6 ka) shows rapid rates of sea-level rise, expansion of estuaries, and a decrease in non-marine deposition with cool and dry climate. Phase D (5.6–4.2 ka) is a time of high rates of sea-level rise, expanding estuaries, and dry and cool climate; the Atlantic shoreline transgressed rapidly and there was little to no deposition on the uplands. Phase E (4.2–1.1 ka) is a time of lowering sea-level rise rates, Atlantic shorelines nearing their present position, and marine shoal deposition; widespread non-marine deposition resumed with a wetter and warmer climate. Phase F (1.1 ka-present) incorporates the Medieval Climate Anomaly and European settlement on the Delmarva Peninsula. Chronology of depositional phases and coastal changes related to sea-level rise is useful for archeological studies of human occupation in relation to climate change in eastern North America, and provides an important dataset for future regional and global sea-level reconstructions.

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Revision of Tenticospirifer Tien, 1938, and similar spiriferid brachiopod genera from the Late Devonian (Frasnian) of Eurasia, North America, and Australia

Journal of Paleontology ◽

10.1017/s0022336000031711 ◽

2000 ◽

Vol 74 (3) ◽

pp. 444-463 ◽

Cited By ~ 10

Author(s):

Xueping Ma ◽

Jed Day

Keyword(s):

North America ◽

Sea Level ◽

South China ◽

North American ◽

Type Species ◽

Western Europe ◽

Late Devonian ◽

Carbonate Platforms ◽

The North ◽

New Family

The cyrtospiriferid brachiopod genus Tenticospirifer Tien, 1938, is revised based on restudy of the type species from the Frasnian (Late Devonian) of the Russian Platform. As revised the genus includes cyrtospiriferid species with pyramidal ventral valves, catacline ventral interareas, a narrow delthyrium, few sinal plications, and lack a median dorsal septum and pseudodeltidium. All species retained in the genus are of Givetian and Frasnian age. All Famennian age species described from South China and North America are rejected from the genus. It appears that Tenticospirifer evolved during the early Givetian in western Europe and remained endemic to that region during the remainder of the Givetian. Successive migrations of Tenticospirifer from eastern Laurussia to North America, then to South China and possibly Australia, coincided with middle and late Frasnian eustatic sea level rises, respectively. The North American species Spirifera cyrtinaformis Hall and Whitfield, 1872, and related species identified as Tenticospirifer by North American workers, are reassigned to Conispirifer Lyashenko, 1985. Its immigration to and widespread dispersal in carbonate platforms of western Laurussia, northern Gondwana and tropical island arcs (?) coincided with a major late Frasnian eustatic sea level rise. The new family Conispiriferidae is proposed with Conispirifer Lyashenko, 1985, selected as the type genus. The new family also includes the new genus Pyramidaspirifer with Platyrachella alta Fenton and Fenton, 1924, proposed as the type species. The affinity of the new family remains uncertain pending restudy of key genera currently included in the Superfamily Cyrtospiriferoidea. Available data from the Devonian brachiopod literature indicate that species of Pyramidaspirifer are restricted to late Frasnian deposits of central and western North America.

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An enigmatic blastozoan echinoderm fauna from central kentucky

Journal of Paleontology ◽

10.1666/08-104.1 ◽

2009 ◽

Vol 83 (5) ◽

pp. 739-749 ◽

Cited By ~ 7

Author(s):

Colin D. Sumrall ◽

Carlton E. Brett ◽

Troy A. Dexter ◽

Alexander Bartholomew

Keyword(s):

North America ◽

Northwest Territories ◽

Middle Devonian ◽

Fossil Record ◽

Foreland Basin ◽

Late Ordovician ◽

Upper Devonian ◽

Range Extension ◽

First Report ◽

Appalachian Foreland

A series of small road cuts of lower Boyle Formation (Middle Devonian: Givetian) near Waco, Kentucky, has produced numerous specimens of three blastozoan clades, including both “anachronistic” diploporan and rhombiferan “cystoids” and relatively advanced Granatocrinid blastoids. This unusual assemblage occurs within a basal grainstone unit of the Boyle Limestone, apparently recording a local shoal deposit. Diploporans, the most abundant articulated echinoderms, are represented by a new protocrinitid species, Tristomiocystis globosus n. gen. and sp. Glyptocystitoid rhombiferans are represented by isolated thecal plates assignable to Callocystitidae. Three species of blastoids, all previously undescribed, include numerous thecae of the schizoblastid Hydroblastus hendyi n. gen. and sp., the rare nucleocrinid Nucleocrinus bosei n. sp., and an enigmatic troosticrinid radial. The blastoid Nucleocrinus is typical for the age; however, the callocystitid, schizoblastid, and protocrinitid are not. Hydroblastus is the oldest known schizoblastid. Middle and Upper Devonian callocystitids have been previously reported only from Iowa and Michigan USA with unpublished reports from Missouri USA and the Northwest Territories, Canada. This occurrence is thus the first report of a Middle Devonian rhombiferan from the Appalachian foreland basin. Tristomiocystis is the first known protocrinitid in North America and the only protocrinitid younger than Late Ordovician. This occurrence thus represents a range extension of nearly 50 million years for protocrinids. This extraordinary sample of echinoderms in a Middle Devonian limestone from a well-studied area of North America highlights the incompleteness of the known fossil record, at least in fragile organisms such as echinoderms.

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Review of the Devonian camerate crinoid Bogotacrinus scheibei Schmidt from Colombia

Journal of Paleontology ◽

10.1017/s0022336000029103 ◽

1987 ◽

Vol 61 (4) ◽

pp. 750-757 ◽

Cited By ~ 1

Author(s):

George C. Mcintosh

Keyword(s):

North America ◽

Western Europe ◽

Lower Devonian ◽

Appalachian Basin ◽

Upper Devonian ◽

Eastern North America ◽

Late Devonian ◽

Early Devonian ◽

Lower Upper

Two recently collected specimens of Bogotacrinus scheibei Schmidt, 1937, from the Devonian (Emsian–Eifelian) Floresta Formation of Colombia reveal that Bogotacrinus is a dicyclic camerate crinoid genus closely related to Pterinocrinus Goldring, 1923 (Lower–Upper Devonian of eastern North America and western Europe), and Ampurocrinus McIntosh, 1981 (Lower Devonian of Bolivia). The new diplobathrid camerate crinoid family Pterinocrinidae, characterized by species with low conical dicyclic cups and rami composed of compound, bipinnulate brachials, is herein proposed to accommodate these three genera. This family originated in western Europe and migrated into the Malvinokaffric and southern Eastern Americas Realms during the Early Devonian and into the northeastern Appalachian Basin by the Late Devonian.

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Vetupraeca n. gen. and Mucopraeca n. gen. (Cryptodonta, Bivalvia): A reappraisal of Late Devonian bivalves from the Hercynian Facies

Journal of Paleontology ◽

10.1017/s0022336000055359 ◽

2008 ◽

Vol 82 (6) ◽

pp. 1150-1160

Author(s):

Judith Nagel-Myers ◽

Michael R. W. Amler ◽

R. Thomas Becker

Keyword(s):

North America ◽

Outer Shelf ◽

Eastern North America ◽

Late Devonian ◽

New Genera ◽

Hercynian Facies

Bivalves from the Late Devonian pelagic or Hercynian Facies of classical regions such as eastern North America and Europe have not been investigated for almost a century.A group of small, radially ribbed bivalves frequently occurs in association with ammonoids and conodonts in pelagic cephalopod limestones and shales of the latest Frasnian and early Famennian. These bivalves have traditionally been assigned to the Late Silurian genus Praecardium Barrande, 1881. Re-studying the types of the Late Devonian taxa, Cardium? vetustum Hall, 1843, Cardiola duplicata Münster, 1840, Praecardium clymeniae Beushausen, 1895, Praecardium melletes Clarke, 1904, and Praecardium multicostatum Clarke, 1904 shows that they differ significantly from Praecardium.As a result, two new genera, Vetupraeca n. gen. and Mucopraeca n. gen, are established. Furthermore, neotypes are designated for Cardiola nehdensis, Kayser, 1873 and Vetupraeca clymeniae (Beushausen, 1895), and lectotypes are chosen for Mucopraeca multicostata (Clarke, 1904) and Vetupraeca duplicata (Münster, 1840). These bivalve taxa were widely distributed in the subtropical to tropical, latest Frasnian/early Famennian outer shelf habitats of Laurussia and Gondwana.

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The youngest styliolines and nowakiids (Late Devonian) currently known from New York

Journal of Paleontology ◽

10.1017/s0022336000022216 ◽

1986 ◽

Vol 60 (3) ◽

pp. 689-700 ◽

Cited By ~ 7

Author(s):

Ellis L. Yochelson ◽

William T. Kirchgasser

Keyword(s):

New York ◽

North America ◽

Wall Structure ◽

Eastern North America ◽

Late Devonian ◽

Appalachian Region ◽

The West ◽

First Report

This is the first report of styliolines in the Angola Shale Member of the West Falls Formation in western New York. These specimens are of late Frasnian age and are the youngest individuals known from the Appalachian Region. This upward extension of range places the extinction of styliolines in eastern North America more in accord with their time of extinction in Europe. Nowakiids have also been found in the younger Hanover Shale Member, in the upper part of the Java Formation, also of late Frasnian age. These are the youngest known nowakiids from the Appalachians. Within the limits of preservation, the external characters and wall structure of the Angola styliolines are comparable with those of older specimens. The associated rare small annulated nowakiids and homotcenids have a laminated wall structure fundamentally different from that of the styliolines.

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